The notion of providing retractable devices is not new. For many years, a wide variety of industries have used retractable devices such as keyboards and displays. These are just two examples of user interface devices that may be used in a deployed position and then retracted when they are not needed or otherwise intrude into a cluttered space.
The aircraft industry has long used retractable user interface devices because of the limited operational space that is available either in the cockpit or in the passenger compartment of an aircraft. It is not uncommon to discover retractable keyboards that are used to control equipment disposed in the flight deck. Once the keyboard is not needed, it can be stowed so that it does not continue to clutter the operating space. This helps to promote the operational safety of the aircraft. Although not as common, retractable display devices may also be used in the flight deck.
In the passenger compartment of an aircraft, retractable display devices are much more prevalent. In many cases, retractable display devices may comprise an in-flight entertainment (IFE) system. For instance, retractable display devices may be used to present entertainment content to passengers. Retractable display devices that may be used in IFE systems may take on many different forms. One example of a retractable display device is that of a personal display unit that may be stowed in the arm of a passenger seat. When the display is in use, it may be deployed outward from the passenger seat arm and articulated into a comfortable viewing position. Another form of retractable display device that may be used in IFE applications is that of an overhead monitor. An overhead monitor is typically installed in the ceiling of the passenger compartment or it may be disposed at the bottom surface of luggage compartments. When an overhead monitor is installed in either of these manners, it typically deploys downward into the passenger space.
Other example applications of retractable display devices and keyboards may be found in the automotive industry. Here, stereo systems, navigation systems and automotive control systems may benefit from the application of retractable displays and keyboards. For instance, a deployable heads-up-display may be disposed above the control console of an automobile. The heads-up-display may be used to enhance night vision. In this type of an application, it would be beneficial to retract the heads-up-display when it is not needed. Even some stereo systems meant for use in cars may comprise deployable keyboards because of the limited amount of space available on the console for conventional controls.
The most advanced of these deployable user interface devices comprise mechanisms for automatic deployment and retraction of the user interface assembly. It is not uncommon to find a retractable overhead display installed in the passenger compartment of an aircraft that automatically responds to a deployment signal. When the deployment signal is active, this type of overhead display deploys the functional-end of the display screen into the passenger space. Likewise, when the deployment signal becomes inactive, the display screen may be retracted; promoting passenger comfort and safety.
In all of these cases, automatic deployment and retraction of a user interface provides a significant level of convenience. However, as with any mechanized assembly, there exists the potential to harm human life and limb. Up until now, deployable user interface devices that are automatically driven into the user's space have done so using a constant force. If allowed to operate in this type of an unrestrained fashion, deployment of a user interface assembly may inadvertently apply harmful pressure to an innocent bystander.
Despite the convenience they offer, automatically deployed user interface devices such as keyboards and displays rigidly maintain their deployment position. There may be situations where a deployed user interface assembly must be retracted in an exigent circumstance. One such situation is commonly encountered in an aircraft application of an overhead display; a passenger inadvertently collides with the deployed display screen comprising the display assembly. In this case, it is likely that the passenger will sustain physical injury if the fully deployed position is rigidly maintained.